Vulnerability · Published Oct 27, 2026 · Assigned by GitHub_M

CVE-2026-58496ThorVG: Out-of-bounds Read in SFNT/TTF Font Loader via Memory API

Medium 4.3

In plain English

A medium-severity out-of-bounds read in thorvg from thorvg. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 11% of all known vulnerabilities).

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.2%top 88.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Thor Vector Graphics (ThorVG) is a production-ready vector graphics engine. Prior to 1.0.7, the `SFNT/TTF` font loader's `SfntLoader::gen` function in `tvgSfntLoader.cpp` reads `data[0] through data[3]` to identify the font type without first checking that the input buffer contains at least four bytes. Loading an undersized font directly from memory through public APIs such as `tvg::Text::load` causes an out-of-bounds read. Loading through a file path using `mmap` can mask the read because of page alignment; the memory-loading API directly exposes it. Depending on memory layout, a malformed short font may crash the consuming application or disclose adjacent heap memory. This issue is fixed in version 1.0.7.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:14	thorvg	no fix listed	DEBIAN-CVE-2026-58496
Ubuntu:26.10	thorvg	no fix listed	UBUNTU-CVE-2026-58496

Affected products (as reported)

Vendor	Product	Versions
thorvg	thorvg	< 1.0.7

Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

References

https://github.com/thorvg/thorvg/security/advisories/GHSA-crfw-c34f-vqrj x_refsource_CONFIRM
https://github.com/thorvg/thorvg/commit/1dc232a33535946b5eed5fd65e993b13226da0ca x_refsource_MISC
https://github.com/thorvg/thorvg/releases/tag/v1.0.7 x_refsource_MISC